Bone marrow transplantation in chronic myelogenous leukemia.

(CML) is an oncohematotogical disease characterized by a clonal proliferati on concerning the primitive hematopoietic cell. A typical cytogenetic alter ation known as Philadelphia Chromosome (Ph1), a 9:22 chromosomic translocat ion which produces a hybrid gene BCR/ABL, is present in 95% of the patients . Nineteen CML patients (9 female and 10 male) underwent Bone Marrow Transp lantation (BMT). Median age was 32 years (range 9 to 47); 15 of them were i n chronic phase (CP), and 4 in accelerated phase (AP). At diagnosis, all pa tients were Ph1+, BCR/ABL+. The conditioning regimen consisted of busulphan and cyclophosphamide while patients in AP received etoposide as well. Seve nteen patients received ciclosporine A, methotrexate and methylprednisone a s prophylaxis for Graft Versus Host Disease (GVHD) while 2 patients receive d only the first two drugs. The 9.22 translocation was determined by means of RT-PCT technique using the primers NB1+, Abl3, B2A, CA3 and A2. The sens itivity of the method was 1 x 10(-6). Among the 19 patients who entered the protocol, 14 are alive and in clinical, hematological and cytogenetic remi ssion (Ph-1(-)) and 3 patients died due to acute GVHD, 1 due to graft failu re and 1 due to Hemolytic Uremic Syndrome. Of the 4 transplanted patients i n AP, 3 are alive and in complete remission. The patients had a 74% surviva l, with a median follow-up of 655 days. Complete hematopoietic chimerism wa s demonstrated in 16 patients, with the study of 3 loci, D1S80, APO B and D 17S30. No relationship was found between post BMT hybrid BCR/ABL (RT.PCR) p ersistence and disease relapse; the presence of acute and/or chronic GVHD d id not influence the BCR/ABL positivity. In our experience, BMT has proved to be the only therapeutic alternative for CML with complete clinical, hema tological and cytogenetic remission and a mean survival of 74%, comparable to the international experience.